Microtus fortis Büchner
Fig. 25
Baculum: Stalk large, greatest length (3.8 mm.) 14/5 times greatest breadth, 4½ times greatest depth; three digitate processes ossified; median ossification almost 1/3 length of stalk; lateral ossifications slender, smaller than median ossification; posterior profile of stalk in dorsal view trilobate, basal tuberosities well developed, confluent medially; in end-view dorsal concavity broader and deeper than ventral concavity; medial constriction pronounced (less than ½ greatest depth); lateral profile at widest point of stalk convex, becoming abruptly concave as the flange of the basal tuberosities grades into the shaft, then gradually converging to narrowest point 1/3 of length of stalk from the terminus; stalk wider than deep in proximal 2/3, circular in cross section in terminal 1/3, slight terminal inflation.
A specimen figured by Ognev (1950:297) has the same general proportions, slender lateral processes, and proximal placement of the point of greatest breadth.
Specimens examined: Two from Chipo-ri, Korea, 60443, 63841.